it's working! thanks guys for all your help! The time is not filtering but the others are! i my filter I had ds__start_time and ds__presenter. Mitch on the tips and tricks forums was thankfully following the same tut yesterday and shared. Thanks guys.
If you have any ideas how I can get my time filtering please let me know - or due to our version of matrix it's limited? Presenter results are also not returning if there is an apostrophe either :(